The study also reports, however, that fewer people 55 and older used guns to kill themselves after the act took effect.

The findings provoked strong words on both sides of the gun-control debate; they were also questioned in an editorial that accompanied the study in Wednesday's Journal of the American Medical Association. The AMA supported the Brady Act.

The National Rifle Association claimed the research supports the notion that gun regulations like the Brady Act have no effect on crime. Advocates of stricter gun laws said the study is not an appropriate measure of the success or failure of the Brady Act.

The findings follow research presented last week by the Center to Prevent Handgun Violence, which estimates that 9,368 lives were saved between 1994 and 1998 because guns were less available to criminals.

The head of the center, Sarah Brady, is married to James Brady, for whom the act is named. Brady was the press secretary wounded and paralyzed in the 1981 assassination attempt on President Reagan.

As implemented in 1994, the Brady Act required licensed dealers to perform background checks and observe a five-day waiting period before selling handguns. In 1998, instant background checks replaced the waiting period requirement.

Eighteen states already met the Brady requirements in 1994.

The lead authors of the study, Georgetown University policy analyst Jens Ludwig and Philip Cook of Duke University, examined national statistics from 1985 through 1997 to compare the Brady law's impact on crime in the 32 states that had to toughen their laws.

The authors noted that homicide and suicide rates had already begun to decline nationwide before 1994, but they assumed those rates would fall faster in ``treatment states'' - those that had to adopt new laws to comply.

Instead, they found no overall difference - except that gun suicides dropped 6 percent among people aged 55 and older in the treatment states, Ludwig said.

Reductions in suicides also were seen in other age groups but the numbers were not statistically significant, Ludwig said. Suicides are comparatively common in older adults, so it's not surprising that the biggest impact would be found in that age group, he said.

National Rifle Association spokeswoman Kelly Whitley said the study ``proves what the NRA has been saying all along. Legislation like the Brady Act ... has no impact on the criminal misuse of firearms.''

But Ludwig acknowledged that the research was not designed to analyze the Brady Act's indirect impact on what is known as the secondary gun market - gun sales by unlicensed dealers - which experts say is the source of a significant number of weapons used in crimes.

The findings show ``the importance of extending regulations like the Brady Act to secondary market sales,'' Ludwig said.

The editorial in JAMA, written by a crime expert not involved with the new study, questioned the meaning of the research and called the Brady Act ``the most important national policy initiative related to firearms in over two decades.''

The editorial's author, Richard Rosenfeld of the department of criminology and criminal justice at the University of Missouri in St. Louis, said the study was limited by a lack of evidence of the Brady Act's impact on firearm trafficking from state to state and by its failure to examine the secondary gun market.

He said the examination of the law's impact on suicide was a strong point of the research.

``Knowledge of how primary market regulations affect the secondary firearms market is the single most important next step in research on how the Brady Act and similar strategies affect levels of criminal violence in the United States,'' Rosenfeld wrote.